Chemical contamination in food is one of the most serious food safety problems. Competitive enzyme-linked immunosorbent assay (Cp-ELISA) is the most widely used analytical tool for detection of food chemical contaminants due to its high throughput, low cost, and straightforward readouts. However, conventional ELISA suffers from low sensitivity, which greatly limits its potential in highly sensitive detection. To fulfill increasingly stringent control requirement for chemical contaminants in food, improving the sensitivity of Cp-ELISA is important and meaningful. In this paper, we will briefly review various emerging strategies for increasing Cp-ELISA sensitivity, including: 1) screening higher affinity antibodies to target antigens; 2) preparing competing antigens with lower affinity to antibodies; 3) employing signal amplification; and 4) introducing novel signal transducer elements. This review will focus on clarifying the underlying mechanisms of these strategies in improving sensitivity and providing a careful comparison. Brief discussion on challenges and future directions will be elaborated.

食品中的化学污染是最严重的食品安全问题之一。竞争性酶联免疫吸附测定（Cp-ELISA）由于其高通量，低成本和直接读数的优点，是用于检测食品化学污染物的最广泛使用的分析工具。然而，常规的ELISA具有低灵敏度，这极大地限制了其在高灵敏度检测中的潜力。为了满足食品中化学污染物日益严格的控制要求，提高Cp-ELISA的灵敏度是重要且有意义的。在本文中，我们将简要回顾提高Cp-ELISA敏感性的各种新兴策略，包括：1）筛选针对靶抗原的更高亲和力抗体；2）制备对抗体亲和力较低的竞争性抗原；3）采用信号放大；和4）引入新颖的信号换能器元件。这篇综述将集中于阐明这些策略在提高敏感性和提供仔细比较中的潜在机制。将详细讨论挑战和未来方向。